Projectile.



' UTE ,STAT

PATENT 'Omron-.

EMIL- GATHMANN, 0F BETHLEHEM, PENNSYLVANIA. 'y

PBQJECTILE.

specification o f Letters; Patent.

Patented May a5,n 1909.

Application l'ed March 11, 1908. No. 420,396.

To allwlzomA 'it may concern Be it known that I, EMIL GATHMANX, a

.citizen of the United States, residing at Bethlehem, orthampton county, State of Pennhardening and teinpering of the large, as medium sizes of armor well as the small an piercing projectiles.

Further objects are to' improve the details of construction of such projectiles.

My invention relates to that type of projectile termed armor piercing shot and shell by those familiar with the art. The head or forward portion of these projectiles are usually made very massive, and the body or rear portion contains a cavity or explosive charge chamber. It is extremely desirable that the head or forward portion of the projectile beso hardened and tempered 'as to en able the 1projectile when impacting with a. suitable ve ocity to penetrate the extremely .hard and tough armor plates yproduced by the Krupp and other systems. At the present date, specificatiepls relating to armor piercing projectiles pre'pi'be a test in which the projectie must peiiforate af hard faced armor plate equal tothe Krupp standard of a thickness of at least one caliber or diameter of the projectile, with ythe requirements that the-re be no breaking or cracking of any portion of t-he latter 4so as to expose the charge cavity.

Although the armor piercing projectiles are atl the present time being made of high grade alloy steels and are hardened and .teinpered with skill and care, a great many projectiles fail to pass the prescribed ballistic test. The most frequentlyoccurring manner A of failures that I have personally witnessed dui'ing the past seven years were diie to the shattering of the head of shelland consequent exposuie or opening of the forward end of the .charge cavity. This danger of shattering or rupturing of the head of the projectile upon impact with modern armor of initial strains, bordering en plate becomesv relatively greater, the larger the size or diameter of the pro'ectile andthe more massive the foi'viiiiden or head.

. Frein-the many ballistic, tests of projectiles that I have witnessed and from the number of'experiments made, I have determined that the shattering and rupturing of the usual construction of armor piercing projectile head, isV due mainly to the excessive initial strains in the mass of the metal com-fv posing the head., which strains are caused by the rapid necessary cooling of the hardening processes,.and the consequent shrinkage of the large mass of the outer portion of the metal u on the-practically unyielding inner a'Xial so 'd core or central mass of met-al, which being thus subjected to'a compression beyond-its normal shrinkage dimensions, ex-

erts an initial outward pressure borderingon rupture. I have seen a great number ofA armor iercing projectiles, the points and heads of W `ch have ruptured spontaneously Within a. short period of 'elapsedtime after hardening treatment.

' In my improved pro'ectile, I so construct .the head portion that t e internal rupturing strains due to hardening treatment as-previ o usly described, will be much reduced or praetically eliminated. In order to obtain a good bursting eiect of the projectile diie to the explosion' of the cavity charge of expte-V sive material, it is essential that the 'cavity be strongly inclosed and that no opening exists through Which the gases would readilv issue Without properly fragmenting the shell.

Several forms of the invention are illustrated in the Iac'e'oii'ipanying drawings, in Which j 'f Figure 1 is a longitudinal central sectionl of a projectile embodying the invention. Fig. 2 is a longitudinal central sect-ion of a portion of a shell embodying the invention. '3 is a. longitudinalsection showing in ed form of barrierseat. f

Similar letters represent like parts throughoutthe drawings. j

The practically cylindrical body A of. the projectile contains a charge chamber B vprovided at its rear end `ivith a threaded C adaptedI to engage with a suitable base plug D. The relatively massive head E is `provided with a centrally located lo tudi.

portion rFig. `1, and the said bush'ing l shown in the various viigures.

its exposed or outer bo massive head portion'E, a barrier block H beine' provided to sejarate the charge cham'- ber from the bore The barrier H is suitably secured at or near the forward end of the charge chamber B, where a seat b is located, and may be built up as shown by bushings M and Flug iT in may be ada ted to carry a shell fuse O if so desired, as shown in Fig. 3. A c'ap L of any desired form is preferably placed over the point of the projectile the 'cap being locked to the head of the projectile bymeans of coils of wire or by stiening co lars as vshown in the various drawing.

In harde the head E of-my' construction of project' e, the mass of metal will contract inwardly in the usual manner due to rapid cooling of the same; the bore F will however allow of an inward movementor flow of the metal as the .natural decrease-in the volume of the head takes place, thusinitial strains such as obtained in a solid headed projectile not occur, as the bore'F proigures .of the vides for an inward flow on displacementv of metal, while heated and plastic, which in the solid headed projectile 1s impossible as the pressure on the inferior solid portion caused y contraction of the 'outer portion results in a reactionary pressure tending to disrupt the said outer ortion.

It is evident, the larger'the projectile the more pronounced. this action, as t'he cooling is creases as the square of the. diameter.` I` would therefore -vary the diameter of thenecess'arily slower with increased diameters, the surface increasing in direct ratio to the diameter, while the volume of me'tal inbore F and' also 'its de th to suit shrinking;

the cali r of the projectile or t ve mass of Ametal in the head of same, thus allowing for increased changes of volume.

If in the hardening treatment, cooling.

from the exterior only is desired, which method I prefer, the bore F is plugged with a suitable material such as fire clay, asbestos or the like so that the coolingmedium not act on the same directly..

It will be evident that my invention may be embodied in other forms than those illus- 615A trated.' e

Therefore, without m 'self to the precise construction illustra and describelI,1 I claimz 1l 1 armor piercing project' e comprising a body a tapering head apertured point both formed integral thereand a seat for a plug located between the said bore ld'the charge chamber. 1l.

9 2. armor piercing project' ve comprising' a body bearingy a tapering head and nn apertured-point both formed inte l therewith a charge chamber within the dy a reduced bore ta'per'ed head portion ari/d a; plug/secured between the said charge chamber and the bore.

apertured POD both formed inte with a charge chamber Within the dy a reduced bore within the tapered portion ofA the head and an inserted barrier separating. the bore-fiplm said chamben 1l 4. armor piercing roject' comprising a body bearing a conie head non-apertured point both formed" integral therewith bore wlthin theconical portion ofthe .head

tween the bore and the sai cavity.

its body taperedhead ed to engage a barrier plug locatedbetween .the sacll1 caviti e s. 6. armor. pierc' rojec formed in one piece'its y, ta and point, a charge cavity in the i't-y of smaller diameter the'.

cavities in combination with a soft metal cap mounted on the point of 'said projectile.

7. A projectile having formed in one piece cavity 1n the -bodya smaller'cavity within the 'tapering head and a seat adapted to enf gage a barrier 'located between the said cavities in combination with a soft metal cap mounted on the point of said projectile.

- 8. A projectile formed in one piece its body tapered head and point, the outer formed by com eund curved lines, a charge cavity within t e body. and a smaller cavity within the tapered head and a seat adapted to engage cavities.

' 9. A projectile having formed in one piece its 'body tapered head and point, the outer contourl of the s aid head and point being formed by compound curved lines, a c chamber within the body and a smaller and non-y with, a charge chamber within the body axial bore within the tapered head portion 3. An armor piercing projectile comprising. a body bearing a tapering head and non-. i

al thereand a threaded seat for a 5'. A projectile. having formed ill Qllpieee int. L

shaped cavity within the bodlyoa smaller cav-i ity within the' tapered head and fg. seat'adaptya cav- V its body, tapering head and point, acharge' a barrier plug located between said.

a charge cavity'within the bodyv atreduced ici tape head'and a barrier'interposed between contour of the said. head and point being 4chamber within the tapered head, a seat 1:

, adapted t0 engage baiiiei plug located be- Within the bodyT and smaller chamberflol tween said chambers in combination with e cated in the tapered hea-d and a barrier plug f y metal cap mounted upon the point of said located between said 'chambers for the purprojeetile. pose set forth, l I

10. -A projectile having formed in one piece EMIL GATHMANN J its-body'tapered heed and point, the outer Witnesses: contour of said head and point being formed y PAUL J. GATHMANN,

byeompound curved lines, a chargechamber OTTO E; GATHMANN. 

